Process of making paper-pulp



UNITED STATES PATENT OFFICE.

NORMAN H. BROKAVV, OF KAUKAUNA, WVISCONSIN.

PROCESS OF MAKING PAPER-PULP.

SPECIFICATION forming part of Letters Patent No. 474,944, dated May 17, 1892.

' Application filed April 11 ]891. Serial No. 388,589. (No specimens.)

To all whom it may concern.-

Be it known that I, NORMAN H. BROKAW, a citizen of the United States, residing at Kaukauna, in the county of Outagamieand State of Wisconsin, have invented certain new and useful Improvements in Processes of Making Paper-Pulp, ofwhich the following is a specification.

The object of my invention is to manufacture paper-pulp from pine and other resinous Wood by a process involving the use of sulphit gtli me or similar sulphite.

In carrying out my improvements I take pine or other resinous wood, cut it into sticks of con venient size for handliu gsay fourfeet, or thereaboutand place the sticks in a steam box or vessel, where, by steaming or steeping it, I dissolve the resin, pitch, and tarry matter and separate it from the fiber. The sticks of Wood thus freed from resin, &c., are removed from the steam-box, cooled, and dried, and then cut into disks or chips of suitable size for treatment in a digestcr of ordinary construction, where the Wood is converted into pulp or cellulose under the influence of bisulphite of lime or similar sulphite in the usual way. 1

By my process I can produce cellulose from resinous woods of as good a commercial quality as that produced from spruce or other woods heretofore used.

The steam-box is provided with openings for the ingress and egress 'of steam, and the temperature may vary from 80 to 280 Fahrenheit. It should not be above 280, as it would then discolor the fiber. When a temperature approximating 280 is used, only three or four hours are required to remove the resinous matter. If a temperature as low as 80 be employed, several days are requlred. After the wood is steamed it is removed from the steam box or boiler and allowed to cool. In cooling it dries quickly, as the heat is given 01f. When out up into disks or chips, the Wood is treated in a digesterin the usual way.

I claim as my invention- 1. The herein-described process of making paper-pulp from resinous woods, which consists in steaming or steeping sticks of Wood to remove the resin therefrom, cutting the sticks into disks or chips, and subjectingthem to the action of a sulphite liquor in a digester.

2. The herein-described process of making paper-pulp from resinous Woods, which consists in steaming or steeping sticks of wood to remove the resin therefrom, then cooling and drying the sticks, then cutting them into disks or chips, and then charging them into a digester and treating them with a sulphite solution.

In testimony whereof I have hereunto subscribed my name.

NORMAN H. BROKAW.

Witnesses:

GEORGE W. FARGO, J r., F. A. TOWSLEY. 

